[en] This chapter investigates the subject of intense positron beams. Some new areas of study that might become available with advanced beam technology are reviewed and the terminology is examined. The best radioactive source and moderator available are described. Some details are given on an existing time bunching apparatus and a method of beam bunching is presented. Topics considered include intensity, flux, brightness, phase space density, fluidity, Debye screening, and space charge limitation. Single positron sources are examined